Multi-view video coding (MVC) is the compression framework for the encoding of multi-view sequences. A Multi-view Video Coding (MVC) sequence is a set of two or more video sequences that capture the same scene from a different view point.
It has been widely recognized that Multi-view Video Coding is a key technology that serves a wide variety of applications, including free-viewpoint and 3D video applications, home entertainment and surveillance. In those multi-view applications, the amount of video data involved is enormous. Thus, there exists the need for efficient compression technologies to improve the coding efficiency of current video coding solutions performing simulcast of independent views.
In recent years, much effort has been put in the design of efficient methods for compressing stereoscopic video. Conventional monoscopic compression methods can be applied independently to the left and right views of a stereo image pair. However, higher compression ratios can be achieved if the high correlation between views is exploited.
Regarding a prior art approach in which both views of a stereoscopic image pair are encoded, a Multi-View Profile (MVP) was defined in the International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) Moving Picture Experts Group-2 (MPEG-2) standard to transmit a pair of video signals. MVP relies on a multi-layer signal representation approach such that one view (often the left view) is assigned to a base layer, and the other view is assigned to an enhancement layer. Monoscopic coding with the same tools as Main Profile (MP) is applied to the base layer. The enhancement layer is coded using temporal scalability tools and a hybrid prediction of motion and disparity fields.
In prior art methods relating to the International Organization for Standardization/International Electrotechnical Commission (ISO/IEC) Moving Picture Experts Group-4 (MPEG-4) Part 10 Advanced Video Coding (AVC) standard/International Telecommunication Union, Telecommunication Sector (ITU-T) H.264 recommendation (hereinafter the “MPEG-4 AVC standard”), stereoscopic video coding can be performed in two different ways: (i) as a particular case of interlaced image coding, where all the fields of a particular parity are assigned to the left view and all the fields of the opposite parity are considered the right view of the stereo-view content; or alternatively (ii) by alternating frames from the left and rights views to create a single monoscopic video sequence. A stereovision supplemental enhancement information (SEI) message provides an indication to the decoder of whether or not the coded video sequence represents stereoscopic content and which method was used to encode the corresponding content.
These previously known methods require minimum modifications of existing monoscopic coding techniques. However, they show a limited ability for reducing the redundancy existing between the two views in a stereoscopic pair. As a result, the encoding of stereo-view results in a large overhead when compared to the encoding of a single monoscopic view. Furthermore, there is no previous support for encoding of more than two camera views.